1. Field of the Invention
The present invention relates to a system for anchoring an aircraft on a grating. More particularly, the invention relates to an anchoring system of the type including a harpoon carried by the aircraft and actuated so that a harpoon head becomes anchored in a cell of the grating.
2. Description of the Related Art
Document FR 2 701 689 A1 describes a harpoon equipping an aircraft and able to be pulled towards a landing grating of the aircraft so that the head of the harpoon is fastened on the grating and forms an anchoring point of the aircraft, facilitating the landing operation of the aircraft. According to this document, the harpoon head includes a cylindrical central portion of axis A, and a conical end portion. The central portion includes fingers radially oriented and radially movable between a retracted position and an extended position. The harpoon head also includes means for driving the fingers and keeping them in the extended position in response to the penetration of the harpoon head in a cell of the grating, such that the fingers protrude below the grating and prevent the disengagement of the harpoon.
When the harpoon is fired, there is a high probability that the distal end of the harpoon head will come into contact with an edge surface of the grating, defined by the set of collars separating neighboring cells of the grating. The movement of the harpoon being essentially normal at the edge surface of the grating, the harpoon rebounds on the grating and the anchoring of the aircraft does not occur. It is necessary to restart the anchoring system before trying a new landing phase of the aircraft.
Moreover, during use of the harpoon, the repetition of shocks between the harpoon head and the grating ends up dulling the distal end of the harpoon head. The latter part flattens, such that the harpoon head has an end face which is normal to the axis of the harpoon. In return, the presence of this end face increases the likelihood of the harpoon head coming into contact with the stop surface of the grating. When the harpoon head is too worn for effective anchoring, it is then necessary to replace it, which, given its complex structure, represents a significant cost.